Windows 7 Blue Screen Problem

My Sony 'all-in-one' PC with an I7 processor is about 2 years old and has been performing very reliably until recently. It has now started shutting down every few weeks as a result of a blue screen. I have a jpeg image of this blue screen which shows all kinds of information but does not give solutions to the problem. I have contacted Sony and MS Tech. Support but they only recommend 'Full Recovery' which I am reluctant to do in case valuable data might be corrupted or lost.

Research on the web has indicated that others have experienced this blue screen problem and one of the recommendations is to install a program called 'Whocrashed' which I have done. This analyses the details of the crash and 'dump' and has indicated that the drivers for my Logitech webcam and Nvidia 540T graphics card might be possible causes. Has anyone any other ideas or suggestions?